August 13 C Standard Rationale on mktime; seismo's retirement
Tue Sep 1 16:17:10 UTC 1987
Grunge, I'm not sure I believe this. Now the sole purpose of mktime
is for doing arithmetic on time_t's. What a waste.
Because that's just about what it amounts to if the caller has to set
tm_isdst before calling mktime().
The use that most people want for mktime() is to be able to parse
a string (or whatever) into the tm_hour fields, etc, and then produce
a time_t .. having to second guess whether dst applied at that particular
time is never going to work (and you can't look at the second char of
the zone string and see if it happens to be 'D' .. even assuming that
there is a zone string).
This also doesn't account for time zone changes that skip hours from
one dst timezone to another (when dst changes from +1 hour to +2 hours,
in both cases tm_isdst will be true).
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